All right, George H. W. Bush was the nation's 41st president. His son, George W. Bush, was 43. And yesterday, 43 made the case for 45. President Bush was in South Carolina trying to revive his brother Jeb's campaign ahead of this weekend's primary. It was his first campaign appearance since leaving the White House. NPR national political correspondent Don Gonyea was there.

DON GONYEA, BYLINE: Since leaving office, George W. Bush has been mostly out of the public eye, making news for his hobbies like oil painting.

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GEORGE W. BUSH: But let me assure you, I know that the signature's worth more than the painting.

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GONYEA: But last night, the 43rd president was the star attraction at a rally in North Charleston. With Jeb Bush and former first lady Laura Bush seated nearby on stage, George W. Bush recounted some lighthearted stories about his own past campaigns. But the speech quickly turned serious. He spoke of the moment he became a wartime president on 9/11, saying every president needs to be prepared for the unknown.

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G. BUSH: I've seen Jeb in action. He'll be a strong and steady hand when confronted with the unexpected. Multiple hurricanes hit Florida when I was president and he was governor. He led a robust, well-organized response.

GONYEA: The former president never mentioned any of his brother's rivals by name but repeatedly used lines clearly about Donald Trump.

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G. BUSH: Strength is not empty rhetoric. It is not bluster. It is not theatrics.

GONYEA: And this.

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G. BUSH: And I understand that Americans are angry and frustrated, but we do not need someone in the Oval Office who mirrors and inflames our anger and frustration.

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GONYEA: After about 20 minutes, George Bush handed the mic to Jeb Bush, a candidate who's spent much of the campaign saying voters should see him as his own man and not just as another Bush seeking the White House. But yesterday, he opened with this.

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JEB BUSH: I'm so honored that my brother's here.

GONYEA: He weighed in on the escalating rhetoric between him and Donald Trump. He mocked Trump's repeated assertions that George W. Bush failed to keep America safe because 9/11 happened on his watch. Here is Jeb Bush as his brother looked on last night.

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J. BUSH: And I look back during my brother's time. He didn't know that 9/11 was going to happen. But he rolled up his sleeves, and he inspired us, and he kept us safe. And I'm proud that he did it.

GONYEA: The big question is just how much George Bush helps Jeb Bush in a presidential campaign that's failed to come close to meeting early expectations. The former president is very popular with Republicans in South Carolina, especially with military families. About a thousand people turned out for this evening rally, though the room was only about half full. Some, like Beth and Terry College, a married couple from Mount Pleasant, S.C., do think it will help.

BETH COLLEGE: One hundred percent.

TERRY COLLEGE: Yeah, I mean, I'm sure it's going to help him. You know, there's a lot of people who came here to see 43, and they're going to get to see Jeb while they're here.

GONYEA: Still, they say they are undecided. Meanwhile, 23-year-old Brad Kulac says he loves former President Bush.

BRAD KULAC: I'm here for George.

GONYEA: But he does not think this visit does anything for Jeb Bush, adding...

KULAC: I don't dislike Jeb, but as we stand right now, he probably wouldn't be my primary.